The drugs FEC 100 (5-fluorouracil, epirubicin, and cyclophosphamide) are one of the approved options to treat Locally Advanced or Primary Metastatic Breast Cancer. In this study, the investigators will add another drug called Valproic Acid (VPA) to see whether this makes the treatment better. The addition of Valproic Acid to chemotherapy has been studied in about 65 subjects with cancer and was found to be safe and tolerable. Valproic Acid is approved by the Food and Drug Administration (FDA) for the treatment of seizures, mood swings, and migraine headaches. It is not currently approved for cancer, which is why the investigators are conducting this study.